Apparatus and method for irradiation

ABSTRACT

An apparatus and method for irradiating a fluid containing a material to be irradiated, comprising at least one irradiation chamber having at least one inlet port and outlet port, at least one fluid cooling chamber having at least one inlet port and outlet port, one or more UV radiation sources coupled to the irradiation chamber(s); and at least one heat exchange mechanism thermally coupled to the radiation source(s) and the cooling chamber(s). At least a portion of the interior surface of the cooling chamber(s) may comprise at least a portion of the exterior surface of the irradiation chamber(s) so the cooling chamber(s) is in fluid communication with the irradiation chamber(s).

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.16/101,909, filed on Aug. 13, 2018, which claims the benefit of U.S.Provisional Application No. 62/544,214, filed on Aug. 11, 2017, thedisclosures of which are incorporated by reference in their entireties.

FIELD OF THE INVENTION

The present invention relates generally to systems, apparatus andmethods for disinfection of fluids by irradiation. More specifically,the invention relates to an apparatus, system and method fordisinfection of fluids containing a material to be irradiated.

BACKGROUND OF THE INVENTION

The use of ultraviolet (UV) radiation for the purpose of disinfection ofa fluid, including liquids and gases, is well known. The process ofusing ultraviolet radiation to inactivate microbial contaminants influids is referred to as Ultraviolet Germicidal Irradiation (UVGI).Ultraviolet radiation has also been used for oxidizing organic andinorganic materials in a fluid, termed Advance Oxidation Process (AOP),and many commercial AOP systems are in use today. Systems employing UVGIand AOP methods rely on the ability to transmit UV radiation into thefluid in a predictable manner. The dose of a UVGI system, which hasunits of J/cm², can be simply stated as the product of the UV irradiancein units of W/cm² and the exposure time in seconds.

Both AOP and UVGI require a UV source. For practical purposes, theoutput irradiance of the UV source should be maintained and decay in apredictable manner over the usage lifetime of the UV source. Thisenables predictions about the replacement cycle of the UV source as wellas the overall performance of the system. UV disinfection systems aretypically specified for a certain performance level using a variety offactors, including Reduction Equivalent Dose (RED), End of Lamp Life(EOLL), Ultraviolet Transmittance (UVT) of the fluid, and Fouling (lampwindow and reactor).

Some NSF and EPA regulations require UV disinfection systems to betested with the UV source operating at predicted EOLL optical outputpower. In order to adhere to the UV disinfection system performancespecifications for a predicted time period, the UV source should decayin a predictable manner. There are also commercial benefits to havinglonger EOLL, which leads to longer system lifetimes and/or UV sourcereplacement intervals.

There are many types of UV sources. Historically, low pressure mercuryvapor lamps, medium pressure mercury vapor lamps, and amalgam lamps havebeen used as UV sources for disinfection applications. Other UV sourcesinclude deuterium lamps, light emitting diodes (LEDs), lasers, microplasma sources and solid-state field effect phosphor devices. Microplasma lamps operate on the same principle as the large gas dischargelamps but have a planar electrode generating small localized pockets ofUV emission. Solid state sources such as LEDs create light in asemiconductor material though charge recombination in an active layerwhere charge injection is applied to an anode and cathode of thesemiconductor heterostructure. All of these UV sources have differentoptimal operating temperatures where the IV output flux and/or thelifetime is maximized. Most gas discharge lamps are difficult to operatein very cold ambient conditions because of the lower mercury vaporpressure. Conversely, solid state sources have maximized outputs atlower ambient temperatures. For example, the output power of alow-pressure mercury lamp may peak at an ambient temperature of 40degrees Celsius while the optical output power of a 265 nm LED displaysa linear relationship with ambient temperature. The slope of the LEDcurve may vary by the device design, but the trend remains the same withlarger optical output powers seen at lower ambient temperatures.

Many LED manufacturers specify a maximum junction temperature whichshould not be exceeded. The LED junction temperature is the temperatureof the active layer sandwiched between the n-type and p-typesemiconductor layers of the LED. Exceeding a maximum rated junctiontemperature may result in a decrease in the lifetime or othercharacteristics of the LED. In a simplified model, an LED can berepresented as a series of thermal resistances. For example, a UV LEDpackage may be a surface mount device (SMD) mounted onto a circuitboard, which is itself mounted onto a heatsink or other cooling device.The heatsink may be any heat exchanger or method of cooling, such as apassive heatsink, Peltier device, active airflow, heat pipe, etc. TheLED may be mounted on a variety of electrically and thermally conductivecircuit boards, such as a printed circuit board (PCB), a metal coreprinted circuit board (MCPB), or a chip on board (COB). Every point ofconnection from the junction of the LED itself to the ambientenvironment has a temperature associated with it. These include thejunction temperature of the LED, the temperature between the LED packageat the circuit board, the temperature between the circuit board and theheatsink, and the ambient temperature. At each point of connection, onecan model a thermal resistance, such that R_(JS) is the thermalresistance of the surface mount LED packaged, R_(SB) is the thermalresistance of the circuit board, and R_(BA) is the thermal resistance ofthe heatsink or cooling method. The LED junction temperature can bemodeled as the ambient temperature added to the sum of each of thethermal resistances multiplied by the power lost to heat in the device.This relationship is shown in Equation 1.T _(J(LED)) =T _(Ambient)+Σ_(i)(R _(i) ×P _(Heat))  Equation 1

LEDs are unique among most UV sources in that heat is removed throughthe side of the chip which is electrically connected versus the sidewhich is responsible for most of the UV emission. This is in contrast toa mercury vapor lamp, which has a thermal discharge predominantly in thesame direction as light emission through a quartz sleeve, which alsofunctions as the arc discharge tube. LEDs do not require a quartz windowas they emit light directly from the active layer of the semiconductor,and the light transmits through the subsequent layers of thesemiconductor to exit to the ambient. However, LEDs can be sensitive toelectro-static discharge, moisture, and ambient gases like oxygen ornitrogen which can degrade the performance of the LED electricalcontacts and the semiconductor. For this reason, a quartz window isoften placed on the SMD package of a LED. In UVGI systems where the LEDwill be protected from the fluid via a window, the window on the SMDbecomes superfluous if the above environmental impacts can be mitigated.A single window over a board containing one or more LEDs can be used asthe optical window for a fluid disinfection system if the LEDs aresealed between the board and the window such that the window can sere asa portion of the pressure vessel for the disinfection system and tosegregate the LEDs from the fluid. Potting compounds like epoxies orsilicones can be used between the board and the window to accomplishthis. The potting may be undertaken in a low relative humidityenvironment or even purged with dry air or an inert gas to ensure anyvoids between the LED and window do not have undesirable moisture orgases inside. This would also increase the output power of the LED sinceit would pass light through one quartz window versus two. An additionalbenefit to this type of single window lamp package is that the LEDimparts little heating to the window, in contrast to mercury vaporsources which transmit a large amount of heat to the window. Lowerwindow temperatures have been correlated to less fouling of the window.Window fouling lowers the overall UV transmittance of the window, whichin turn lowers the performance of UVGI and AOP systems. Thus, a robustproduct design utilizing a UV source will account for the temperature ofthe UV source during operation by consideration of heat transfer. Bysuch methods the lifetime and output power of the UV source may bebetter controlled. In addition, methods of assembling the UV source intosecondary packaging can be used to enhance the output power and lifetimeof the UV source.

While the UV source is an important component in a UVGI system, it isonly one component in the overall system efficiency. The systemefficiency can be expressed as the product of the reactor efficiency andthe UV source efficiency. It is good practice in the design of a UVGIsystem to maximize the exposure time, often termed the “residence time”,of the fluid to the UV irradiance thereby maximizing the dose seen bythe fluid. The reactor efficiency is a combination of the residence timeefficiency and the optical efficiency. The optical efficiency of thereactor is a measure of how effectively the reactor uses photons fromthe UV source to increase the probability that a microbial contaminantin the fluid will absorb a photon. One method of increasing thisprobability is to use reflective materials in the reactor such thatphotons from the UV source may be reflected if they are not absorbedduring their initial pass inside the reactor. If there are few absorbersin the fluid and the reflectivity of the material in the reactor ishigh, the photons may be reflected multiple times inside the reactor.

U.S. Patent Application Publications 2012/031749 A1, 2014/0161664 A1,and 2014/0240615 A1, all incorporated herein by reference, disclosevarious apparatus, materials and methods useful herein for disinfectionof fluids by irradiation. However, what is still needed in the art is animproved apparatus and method for irradiation that provides good systemefficiency, incorporates adequate thermal management, and can be usedwith a variety of housings or flow cells, all while maintaining acompact footprint.

SUMMARY OF THE INVENTION

In one embodiment, the invention relates to an irradiation apparatuscomprising: at least one irradiation chamber for a fluid containing amaterial to be irradiated, said chamber having at least one inlet portfor fluid flow into the chamber and at least one outlet port for fluidflow out of the chamber; at least one cooling chamber having at leastone inlet port for fluid flow into the chamber and at least one outletport for fluid flow out of the chamber; one or more UV radiation sourcescoupled to the at least one irradiation chamber; and at least one heatexchange mechanism thermally coupled to the one or more radiationsources and to the at least one cooling chamber, wherein at least aportion of the interior surface of the at least one cooling chambercomprises at least a portion of the exterior surface of the at least oneirradiation chamber, and the at least one cooling chamber is in fluidcommunication with the at least one irradiation chamber.

In another embodiment, the invention relates to a method for irradiatinga fluid containing a material to be irradiated disposed in anirradiation chamber, the irradiation method comprising (1) providing anirradiation apparatus comprising, at least one irradiation chamber for afluid containing a material to be irradiated, said chamber having atleast one inlet port for fluid flow into the chamber and at least oneoutlet port for fluid flow out of the chamber, at least one coolingchamber having at least one inlet port for fluid flow into the chamberand at least one outlet port for fluid flow out of the chamber, one ormore UV radiation sources coupled to the at least one irradiationchamber; and at least one heat exchange mechanism thermally coupled tothe one or more radiation sources and to the at least one coolingchamber; wherein at least a portion of the interior surface of the atleast one cooling chamber comprises at least a portion of the exteriorsurface of the at least one irradiation chamber, and the at least onecooling chamber is in fluid communication with the at least oneirradiation chamber, and (2) irradiating a fluid containing a materialto be irradiated using said irradiating apparatus.

In another embodiment, the invention relates to an irradiation apparatusand method comprising, at least one irradiation chamber for a fluidcontaining a material to be irradiated, said chamber having at least oneinlet port for fluid flow into the chamber and at least one outlet portfor fluid flow out of the chamber, at least one cooling chamber havingat least one inlet port for fluid flow into the chamber and at least oneoutlet port for fluid flow out of the chamber one or more UV radiationsources coupled to the at least one irradiation chamber; and at leastone heat exchange mechanism thermally coupled to the one or moreradiation sources and to the at least one cooling chamber.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is illustrated and described herein with reference to thevarious drawings, in which like reference numbers are used to denotelike apparatus components, as appropriate, and in which.

FIG. 1 is a planar side view illustrating one exemplary embodiment ofthe irradiation apparatus of the invention,

FIG. 2 is a section view of the apparatus of FIG. 1 taken along line2-2,

FIG. 3 is a planar side view illustrating another apparatus of theinvention;

FIG. 4 is a section view of the apparatus of FIG. 3 taken along line4-4:

FIG. 5 is a planar side view illustrating a portion of another apparatusof the invention;

FIG. 6 is a section view of the portion of the apparatus of FIG. 5 takenalong line 6-6;

FIG. 7 is a planar side view illustrating another apparatus of theinvention;

FIG. 8 is a section view of the apparatus of FIG. 7 taken along line8-8;

FIG. 9 is a planar side view illustrating another apparatus of theinvention.

FIG. 10 is a section view of the apparatus of FIG. 9 taken along line10-10;

FIG. 11 is a planar side view illustrating another apparatus of theinvention;

FIG. 12 is a section view of the apparatus of FIG. 11 taken along line1212;

FIG. 13 is a planar side view illustrating another apparatus of theinvention, and

FIG. 14 is a section view of the apparatus of FIG. 13 taken along line14-14.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides an improved UV irradiation apparatus,disinfection system and method which utilizes a secondary reactorchamber to cool the UV source, and in one embodiment, to also increasethe exposure time of the fluid containing a material to be irradiatedinside the system. The UV source directly irradiates a primary reactorchamber with interior surfaces typically made of material whichprincipally reflects the UV radiation and minimally transmits the UVradiation through the material. In one embodiment at least a portion ofthe interior surface of the secondary reactor comprises at least aportion of the exterior surface of the primary reactor chamber. Thesecondary reactor chamber thus receives the fraction of UV radiationtransmitted through the material of the primary reactor. In oneembodiment, the secondary, cooling chamber is in fluid communicationwith the primary, irradiation chamber. Cooling of the UV source isaccomplished via at least one heat exchange mechanism thermally coupledto the UV source and to the fluid in the secondary, cooling chamber.

In another embodiment, the UV irradiation apparatus, disinfection systemand method are designed such that a portion of radiation from the one ormore radiation sources is transmitted from the irradiation chamber intoone or more secondary chambers, including but not limited to a coolingchamber or outlet conduit, such that the radiation disposed to surfacesof the one or more secondary chambers provides a disinfection effect toinhibit the propagation of microbiological contamination. Microbialattachment to surfaces of the irradiation apparatus, hereinafterreferred to as “biofilm” formation, may increase risk to health due topossible transfer of such contaminants to a fluid flowing across suchsurfaces. The inhibition of biofilm within the disinfection system isdesirable since the process of UV irradiation does not impart a residualbiocide to the fluid treated. Fouling of the irradiation apparatus anddisinfection system is most critically avoided in downstream regions ofthe apparatus and system, including but not limited to the ‘last mile’,being later within the process chain than the principle irradiationchamber. In one embodiment, a small portion of the radiation emitted bythe UV source may be redirected to irradiate surfaces of the treatmentapparatus and system. Since the fluid-contact surfaces of the reactorare static, the irradiation period of any segment is equal to the totalperiod for which the UV source is emitting. Thus, far lower irradiancesare required to achieve biofilm inhibition than would be necessary fortransient irradiation, such as for a fluid passing through a reactorchamber. By requiring low irradiance and relatively low UV power, asmall fraction of the power emitted by the source can be scavenged forbiofilm inhibition without significantly impacting the fluiddisinfection performance of the reactor. Thus, a portion of theradiation from the one or more radiation sources can be transmitted tosurfaces of the one or more secondary chambers to inhibit biofilmformation thereon.

In one embodiment of the invention, the apparatus has twothree-dimensional chambers, each of which has at least one inlet portand at least one outlet port for the flow of fluid into and out of thechambers A UV radiation source provides radiation to the interior of oneof the chambers, the irradiation chamber. The radiation source has athermal connection to the other chamber, the cooling chamber. Thisthermal connection is between the backside and/or frontside of a heatexchange mechanism connected to the UV source and the fluid in thecooling chamber. The two chambers are in fluidic connection where theinlet of one of the chambers is the outlet for the other chamber. Theirradiation chamber is typically constructed front a material whichprincipally reflects the UV radiation from the UV source and minimallytransmits the UV radiation. The cooling chamber has at least a portionof its chamber interior comprised of the exterior of the irradiationchamber. UV radiation transmitted through the material of theirradiation chamber thus serves as the IN source for the coolingchamber. This increases the exposure time of the fluid to the UVradiation and increases the dose seen by the fluid. Moreover, theradiation transmitted to surfaces of the cooling chamber inhibitsbiofilm formation thereon.

The UV radiation source (or a plurality of UV radiation sources) maycomprise one or more UV-C radiation sources, or a combination thereof.The UV radiation source (or plurality of UV radiation sources) istypically coupled to a support structure in or on a wall of theirradiation chamber or the cooling chamber. The support structure holdsthe UV radiation source(s), which may be UV-C radiation source(s), suchthat they selectively direct UV radiation into the interior of anirradiation chamber in which a material to be irradiated is selectivelydisposed. Peak wavelengths may be (dynamically) selected and/oradjusted, and a plurality of wavelengths may be utilized such that theaction spectrum of a given organism can be targeted, thus improvingdisinfection efficiency. For example, one or more wavelengths of the onemore UV radiation sources may be selected based on an identification ofa contaminant in the material to be irradiated. The one or more UVradiation sources may deliver one or more wavelengths, or a combinationof wavelengths, to the material to be irradiated. The wavelengths mayinduce fluorescence in the material to be irradiated thereby allowingfor the identification of the contaminant in the material to beirradiated. Optionally, the material to be irradiated may be disposedadjacent to an n-type single crystalline semiconductor to generatehydrogen peroxide at the semiconductor surface through bandgap electricphoto-excitation for disinfection. Heat is managed, and optionallyrecuperated, using a heat exchange mechanism, such as one or more of athermoelectric cooling device, a vapor chamber, a heatsink, a heatdissipation structure, a fan, a thermal transfer material, a materialthermally coupled to a fluid, and a cooling coating, disposedsubstantially adjacent to the UV radiation source(s). In one embodiment,the heat exchange mechanism is a heatsink or a thermal transfermaterial, or combinations thereof. The irradiation apparatus may be mademoisture resistant using a moisture seal and desiccant coupled to and/ordisposed within the support structure. The irradiation assembly caninclude a monitoring/detection mechanism and control circuitry fordynamically controlling the delivery of UV radiation to the material tobe irradiated based on flow rate, water quality, user input, or otheroperating conditions. Finally, associated performance data may be storedin an onboard or external data storage unit.

In various embodiments of the invention, a modular semiconductor UV LEDmounting configuration may be provided including a IN radiation sourcepackage containing a single LED or multiple LED “dice” arranged in amatrix or array. The LED dice can be selected to provide multiplewavelengths in both the UV and visible radiation spectrum from about 200nm to about 800 nm. In one exemplary embodiment, the matrix or arrayincludes LED dice emitting wavelengths in the range of about 200-320 nmin order to saturate the absorption mechanism of nucleocapsids (withpeak emission centered at around 280 nm), and at the same time to targetthe peak absorption of nucleic acid with its peak emission wavelengthspanning about 250-280 nm. In another exemplary embodiment, with theintention of mimicking the optical output spectrum of low or mediumpressure Hg-based UV lamps used to target various bacteria and viruses,the matrix or array of LED dice utilizes multiple wavelengths, includingat least one of about 240-260 nm, about 260-344 nm, about 350-380 nm,about 400-450 nm, or about 500-600 nm. A further exemplary embodiment isa matrix or array of LED dice emitting germicidal wavelengths rangingfrom about 250 nm to 300 nm in conjunction with LED dice emittingwavelengths in the range of about 350 nm to 400 nm to enablephotocatalytic oxidation of pathogens or pollutants in water inproximity of crystalline films of n-type semiconductors, such as TiO2,NiO, or SnO2. A still further exemplary embodiment is a modular mountingconfiguration containing multiple LED dice emitting about 250-320 nm andabout 320-400 nm wavelengths arranged in a matrix or array to enable thefluorescence spectra of NA DII, and tryptophan, of particles withbiological origin. In another exemplary embodiment, a commerciallyavailable SETi UV Clean™ LED package is used. Individual LED dice or asingle die bonded to a thermally conductive metal core circuit board(MCPCB), such as those available from The Bergquist Company™, may alsobe used.

The LED package may be connected to a heat dissipation sink, which is inturn configured to mount to a window port of the irradiation chamber.The mounting face of the module may possess a seal or gasket, whichencloses the LED package along with a desiccant, thus reducingcondensing moisture. The heatsink may be round, square, or anothersuitable shape. Heat from the LEDs is optionally conducted by the aid ofa thermoelectric cooler or other means to the heatsink, which isoptionally cooled by forced air. The LED package may be electricallyconnected to control and power circuitry, which is included as part ofthe replaceable module. Circuitry is included within the replaceablemodule in order to provide telemetric data and track information, suchas operating temperature and run time.

A packaged UV LED, or a matrix or array of multiple UV LEDs may beattached to the heatsink. Multiple UV wavelengths can be used tooptimize the effect on specific microorganisms. Backside heat extractionmay be aided by thermoelectric cooling (TEC) and/or a vapor chamber.Additionally, the UV LED package may be topside cooled by conductionthrough a highly thermally conductive over-layer, such as siliconepolymer impregnated with diamond nanoparticles, which may have a singlecrystalline structure.

The surface of the metal portion of the heatsink and UV radiationemitting housing may be flat for mounting the LED and accessory dies orpackages; or optionally recessed in order to provide a concavereflective structure for the LEDs and/or to provide means forattachment. The heatsink may be attached to the irradiation apparatus bya variety of methods, including, but not limited to, contact adhesion,spring pins, clamps, clips that swivel, screws, by screwing in anexemplary embodiment of the heatsink with a rounded bezel that hasthreads cut into it, or by twisting in an exemplary embodiment of theheatsink with a rounded bezel which connects by means of a bayonetconnector.

Components for the electrical and/or electronic control of the UVradiation source may optionally be included within the sealed unit aspreviously described, such that they may act upon the UV radiationsource whilst maintaining protection from the external environmentthrough such hermiticity, the use of desiccants, or a combinationthereof as previously described. Further, the co-location of thesecomponents onto the MCPCB, or otherwise, and subsequent thermal union tothe heat exchange mechanism may be used to extract heat generated by,for example power conversion components. Additionally, these electricaland/or electronic components may include sensors by which the operatingconditions and status of the UV radiation source may be determined,including but not limited to a photodiode, thermocouple, thermistor,acoustic sensor, hall probe, current probe, etc.

The radiation emitter module may be a user replaceable unit, optionallyincluding attached electronics and desiccating materials in order tocombat moisture and humidity. Attached electronics can include anindividual identification number and telemetry tracking, as well as aninterconnect for easy disconnect from a larger system.

Cooling of the LED package may be assisted by a TEC or vapor chambersituated between the LED package and the heatsink. The TEC may take theform of a single TEC, or multiple modules situated to provide contactaround irregular package geometry, such as a through-hole design.Furthermore, electro-thermal modules may be included to harvest energyfrom the waste heat created.

The UV radiation may be transmitted from the LED dice through atransmissive window, polymer, air, and/or aperture into the irradiationchamber. The transmissive window has a transmission spectrum appropriatefor the choice of LEDs used, for example the UV-C range.

Referring now to FIGS. 1 and 2 , in one exemplary embodiment of theinvention, the irradiation apparatus A includes two three-dimensionalchambers 1 and 2, each having an inlet port and an outlet port for theflow of a fluid into and out of the chambers. Irradiation chamber 1 hasinlet port 4 for fluid flow into the chamber and outlet port 5 for fluidflow out of the chamber. Cooling chamber 2 has inlet port 3 for fluidflow into the chamber and outlet port 4 for fluid flow out of thechamber. Cooling chamber 2 and irradiation chamber 1 are in fluidicconnection and in fluid communication, with port 4 functioning as boththe outlet port for the cooling chamber and the inlet port for theirradiation chamber. A UV radiation source 6 provides radiation to theinterior of irradiation chamber 1. The radiation source has a thermalconnection to the cooling chamber 2. This thermal connection is betweenthe backside and/or frontside of at least one heat exchange mechanismthermally connected or coupled to the radiation source and to the fluidin the cooling chamber. In one embodiment, the heat exchange mechanismis heatsink 8. A single, quartz optical window 7 is placed over the UVradiation source 6 to protect it from fluid in the irradiation chamber1. The UV radiation source is sealed between the heat exchange mechanismand the window such that the window serves as a portion of the pressurevessel for the disinfection system and to segregate the UV radiationsource from the fluid in the irradiation chamber.

Irradiation chamber 1 is typically constructed from a material whichprincipally reflects the UV radiation front the UV source and minimallytransmits the UV radiation. At least a portion of the interior surfaceof the cooling chamber 2 comprises at least a portion of the exteriorsurface of the irradiation chamber 1. The interior surface of thecooling chamber (or chambers) typically comprises at least a substantialportion of the exterior surface of the irradiation chamber(s), moretypically substantially all of the exterior surface of the irradiationchamber(s), such that the cooling chamber(s) substantially or completelyenclose the irradiation chamber(s). In one embodiment, the totalexterior surface of the one or more irradiation chambers in theirradiation apparatus is at least about 20%, typically at least about30%, more typically at least about 40%, of the total interior surface;of the one or mon cooling chambers in the irradiation apparatus. The UVradiation transmitted through the material of chamber 1 serves as the UVsource for cooling chamber 2. Thus, the dose, D_(m), received by anyparticle flowing through the two chamber system described can beexpressed by the following equationD _(m) =t _(A)φ_(A) +t _(B)φ_(B)where t_(A) and t_(B) are the residence times of the particle inchambers 1 and 2, respectively, and φ_(A) and φ_(B) are the radiometricflux seen by the particle in chambers 1 and 2, respectively.

In another embodiment, the UV source is a LED which is in electrical andthermal connection to a thermal transfer material, such as a metal coreprinted circuit board (MCPCB), printed circuit board (PCB) or otherdielectric material. The thermal transfer material is in direct contactwith the fluid in cooling chamber 2, providing a thermal path betweenthe LED and the fluid. In this case, the fluid will provide cooling tothe LED if the fluid, e.g., water, temperature is lower than thejunction temperature. The thermal transfer material functions as a heatexchange mechanism thermally connected or coupled to the radiationsource and to the fluid in the cooling chamber.

In another embodiment, the UV source is a LED which is in electrical andthermal connection to a thermal transfer material, such as a metal coreprinted circuit board (MCPCB), printed circuit board (PCB) or otherdielectric material, which is in contact with a separate, second thermaltransfer material in direct contact with the fluid in the irradiationchamber 1, providing a thermal path between the LED and the fluid. Inthis case, the fluid will provide cooling to the LED if the fluid, e.g.,water, temperature is lower than the junction temperature. The secondthermal transfer material may be a metal, dielectric, semiconductor,plastic or any other thermally conductive material. The thermal transfermaterial functions as a heat exchange mechanism thermally connected orcoupled to the radiation source and to the fluid in the cooling chamber.

In another embodiment, the cooling chamber 2 also serves to increase thestructural integrity of the combined system shown in FIGS. 1-2 such thatthe pressure rating of the entire system (chambers 1 and 2) isincreased. For example, the cooling chamber may be made of a materialhaving a higher tensile strength than the material used to make theirradiation chamber.

In another embodiment, optical coupling between the irradiation chamberand the one or more cooling chambers or other secondary chambers may beaccomplished via one or more portholes through the interior of theirradiation chamber to allow for UV radiation to enter the cooling orother secondary chambers from the irradiation chamber. The porthole(s)may also be in fluidic connection to the cooling chamber(s) and increasefluid communication between the irradiation and secondary chambers.Radiation transmitted through the porthole(s) to surfaces of the coolingor other secondary chambers inhibits biofilm formation on their surfacesand possible microbial contamination in downstream regions of theapparatus. Thus, a portion of the fluidic outlet structure of theirradiation apparatus may be optically coupled to the irradiationchamber, either through direct illumination through one or moreportholes or other openings in the irradiation chamber or via partialtransmission through the material of the chamber, such that the surfacesof the outlet structure are irradiated to inhibit biofilm formationthereon. The UV radiation may be used as a biofilm inhibitor within anintegrated UV disinfection apparatus, system and method. This mayinclude intelligent control of the apparatus, system and method withperiodic “on cycles” during periods of non-use, such that a constantbacteriostatic effect may be imparted in one embodiment, opticalcoupling between the irradiation chamber 1 and cooling chamber 2 may beaccomplished via at least one small porthole through the interior ofchamber 1 to allow for UV radiation to enter chamber 2 from chamber 1.The porthole(s) may also be in fluidic connection to chamber 2 andincrease fluid communication between chambers 1 and 2. The radiationtransmitted to surfaces of chamber 2 through the at least one smallporthole and via partial transmission through the material of chamber 1also inhibits biofilm formation on surfaces of chamber 2 and possiblemicrobial contamination in downstream regions of the apparatus.

In another embodiment of the invention, the UV source transmitsradiation to an irradiation chamber and is thermally coupled to acooling chamber that is structurally distinct from the irradiationchamber. In the embodiment shown in FIGS. 3 and 4 , the irradiationapparatus B includes two three-dimensional chambers 9 and 10, eachhaving an inlet port and an outlet port for the flow of a fluid into andout of the chambers. Irradiation chamber 9 has inlet port 12 for fluidflow into the chamber and outlet port 13 for fluid flow out of thechamber. Cooling chamber 10 has inlet port 11 for fluid flow into thechamber and outlet port 17 for fluid flow out of the chamber. However,cooling chamber 10 and irradiation chamber 9 are structurally distinctand not in fluidic connection or fluid communication. A UV radiationsource 14 provides radiation to the interior of irradiation chamber 9.The radiation source has a thermal connection to the cooling chamber 10.This thermal connection is between the backside and/or frontside of atleast one heat exchange mechanism thermally connected or coupled to theradiation source and to the fluid in the cooling chamber in oneembodiment, the heat exchange mechanism is heatsink 14. A single, quartzoptical window 15 is placed over the UV radiation source 14 to protectit from fluid in the irradiation chamber 9. The UV radiation source issealed between the heat exchange mechanism and the window such that thewindow serves as a portion of the pressure vessel for the disinfectionsystem and to segregate the UV radiation source from the fluid in theirradiation chamber. Irradiation chamber 9 is constructed from amaterial which principally reflects the UV radiation from the UV sourceand minimally transmits the UV radiation.

In another embodiment, the irradiation chamber 9 and the cooling chamber10 are dependent upon a single rigid frame for structural stability. Thepartition between the chambers is accomplished with a material that isprimarily non-structural. In another embodiment, the partition betweenthe chambers is semi-permeable, allowing for fluidic flux betweenchambers.

In another embodiment, the UV radiation source is thermally connected toa thermal transfer material that is partially or entirely coupled to ormounted inside the interior of the irradiation chamber. The thermaltransfer material provides conductive heat transfer from the UV sourceto the fluid in the irradiation chamber via the interior of the chamber.In one embodiment, the UV source is an LED which is in electrical andthermal connection to the thermal transfer material, such as a metalcore printed circuit board (MCPCB), printed circuit board (PCB) or otherdielectric material. The thermal transfer material is in direct contactwith the fluid in the irradiation chamber providing a thermal pathbetween the LED and the fluid. In this case, the fluid will providecooling to the LED if the fluid, e.g., water, temperature is lower thanthe junction temperature. The thermal transfer material functions as aheat exchange mechanism thermally connected or coupled to the radiationsource and to the fluid in the cooling chamber.

In another embodiment, the UV source is an LED which is in electricaland thermal connection to the thermal transfer material, such as a metalcore printed circuit board (MCPCB), printed circuit board (PCB) or otherdielectric material, which is in contact with a separate thermaltransfer material in direct contact with the fluid in the irradiationchamber, providing a thermal path between the LED and the fluid. In thiscase, the fluid will provide cooling to the LED if the fluid, e.g.,water, temperature is lower than the junction temperature. The thermaltransfer material may be a metal, dielectric, semiconductor, plastic orany other thermally conductive material. The thermal transfer materialfunctions as a heat exchange mechanism thermally connected or coupled tothe radiation source and to the fluid in the cooling chamber FIGS. 5 and6 illustrate a portion of one such apparatus of the invention. In oneexample, apparatus B shown in FIGS. 3 and 4 can be modified to includethe apparatus C cooling chamber 21. UV radiation source 18, and heatexchange mechanisms 19 and 20 shown in FIGS. 5 and 6 instead of thecooling chamber, UV radiation source and heat exchange mechanism inFIGS. 3 and 4 . Cooling chamber 21 has inlet port 22 for fluid flow intothe chamber and outlet port 23 for fluid flow out of the chamber. UVradiation source 18 provides radiation to the interior of theirradiation chamber. The UV source is in electrical and thermalconnection with thermal transfer material 19, such as a metal,dielectric, semiconductor, plastic or any other thermally conductivematerial, e.g., a metal core printed circuit board (MCPCB), printedcircuit board (PCB) or other dielectric material. Thermal transfermaterial 19 is in contact with a separate heat exchange mechanism 20,such as a heatsink or another thermal transfer material as describedabove, which is in direct contact with the fluid in the irradiationchamber providing a thermal path between the UV radiation source and thefluid. In this case, the fluid will provide cooling to the UV radiationsource if the fluid, e.g., water, temperature is lower than the junctiontemperature. The radiation source also has a thermal connection to thecooling chamber 21 via the heat exchange mechanisms 19 and 20 thermallyconnected or coupled to the radiation source and to the fluid in thecooling chamber. In another embodiment, the UV source 18 also providesUV radiation to the thermal transfer material 19.

In another embodiment, the UV source is a micro plasma lamp which is indirect contact with the fluid in the reactor irradiation chamberproviding a direct thermal path between the lamp and the fluid. In thiscase, the fluid will provide cooling to the lamp. In the embodimentshown in FIGS. 7 and 8 , the irradiation apparatus D includes athree-dimensional irradiation chamber 23 having an inlet port 24 and anoutlet port 25 for the flow of a fluid into and out of the chamber. Amicro plasma lamp UV radiation source 24 provides radiation to theinterior of irradiation chamber 23. Because the micro plasma lamp is indirect contact with the fluid in chamber 23, it provides a directthermal path between the lamp and the fluid, thereby cooling the lamp.In one embodiment, the micro plasma lamp is in thermal connection with athermal transfer material which is in direct contact with the fluid inthe irradiation chamber, providing a thermal path between the lamp andthe fluid. The thermal transfer material may be a metal, dielectric,semiconductor, plastic or any other thermally conductive material. Thethermal transfer material may reflect a portion of the UV radiationfront the lamp. In another embodiment, the thermal transfer material isin contact with a separate thermal transfer material which is in directcontact with the fluid in the irradiation chamber, providing a thermalpath between the lamp and the fluid. In these cases, the fluid willprovide cooling to the lamp. As such, the embodiment shown in FIGS. 7and 8 may be used as an irradiation chamber in the other irradiationapparatus shown and described herein.

In another embodiment, the invention provides a plurality of UVradiation sources and a plurality of irradiation chambers, each with atleast one inlet and one outlet port. Each UV radiation source isprimarily optically coupled to a single irradiation chamber. Allirradiation chambers are fluidically coupled to a single cooling chambersuch that all fluid that passes through any irradiation chamber alsopasses through the cooling chamber. In this way, the fluidic fluxthrough the cooling chamber is equal to the sum of fluidic fluxesthrough all the irradiation chambers. In addition, all UV sources arethermally coupled to the fluidic flux via the interior of the coolingchamber.

In another embodiment, the invention provides a plurality of UVradiation sources and a plurality of irradiation chambers, each with atleast one inlet and one outlet port. Each UV radiation source isprimarily optically coupled to a single irradiation chamber. All of theUV radiation sources are thermally coupled to the single coolingchamber. One or more of the irradiation chambers is in fluidicconnection, where the outlet of one chamber is the inlet for anotherchamber.

In another embodiment, the invention provides a plurality of UVradiation sources and a plurality of irradiation chambers each with atleast one inlet and one outlet port. Each UV radiation source isprimarily optically coupled to a single irradiation chamber. All the UVradiation sources are thermally coupled to the single cooling chamber.One or more of the irradiation chambers are in fluidic connection, wherethe outlet of one chamber is the inlet for another chamber. In addition,the cooling chamber is in fluid connection to one or more of theirradiation chambers, where the outlet of the cooling chamber is theinlet of one or more of the irradiation chambers.

In the embodiments described above, the plurality of irradiationchambers are fluidically coupled to a single cooling chamber such thatall fluid that passes through any irradiation chamber also passesthrough the cooling chamber. Just as multiple irradiation chambers maybe fluidically coupled to a single cooling chamber, forming a singleunit, sets of these individual units may be arrayed in parallel orseries combinations where the inlet to each unit is composed of afraction of the total inlet flow (parallel case) or the entire flow(series case), or a blend of series and parallel configurations of eachunit.

In the embodiment shown in FIGS. 9 and 10 , irradiation apparatus Eincludes three three-dimensional chambers, two irradiation chambers 31and cooling chamber 27. Each chamber has an inlet port and an outletport for the flow of fluid into and out of the chambers. Eachirradiation chamber 31 has an inlet port 30 for fluid flow into thechamber and an outlet port 28 for fluid flow out of the chamber. Coolingchamber 27 has inlet port 29 for fluid flow into the chamber and twooutlet ports 30 for fluid flow out of the chamber. Cooling chamber 27and irradiation chambers 31 are in fluidic connection and fluidcommunication, with ports 30 functioning as both the outlet ports forthe cooling chamber and the inlet ports for the irradiation chambers. AUV radiation sources 34 provides radiation to the interior ofirradiation chambers 31. The radiation sources have a thermal connectionto the cooling chamber 27. This thermal connection is between thebackside and/or frontside of at least one heat exchange mechanismthermally connected or coupled to each radiation source and to the fluidin the cooling chamber. In one embodiment, the heat exchange mechanismis via each heatsink 33. A single, quartz optical window 32 is placedover each UV radiation source 34 to protect it from fluid in itsirradiation chamber. The UV radiation source is sealed between the heatexchange mechanism and the window such that the window serves as aportion of the pressure vessel for the disinfection system and tosegregate the UV radiation source from the fluid in the irradiationchamber. As described above, each UV radiation source 34 is primarilyoptically coupled to a single irradiation chamber 31. All the UVradiation sources are thermally coupled to the single cooling chamber27. The irradiation chambers 31 are in fluidic connection and fluidcommunication with the cooling chamber 27 and with each other since theoutlets 30 of the cooling chamber are the inlets for the irradiationchambers.

In another embodiment the transfer of heat from the UV source to thefluidic flux is accomplished via conductive heat transfer through anominally flat surface that is incorporated into the surface of achamber, in thermal contact with the fluidic flu within that chamber.For example, in the embodiments shown in FIGS. 2 and 10 , the transferof heat from the UV source to the fluid in the cooling chamber isaccomplished via conductive heat transfer through a nominally flatsurface of the heatsink incorporated into the outer surface of theirradiation chamber and the inner surface of the cooling chamber, whichis in thermal contact with the fluidic flux within the cooling chamber.

In another embodiment, the transfer of heat from the UV source to thefluidic flux is accomplished via conductive heat transfer through aporous structure placed in the flow path of some or all of the fluidicflux. The porous structure may be designed such that the surface area ismaximized to provide for efficient conductive heat transfer to thefluidic flux. The porous structure used for maximizing conductive heattransfer may also promote turbulent mixing of the fluidic flux and/orlaminar flow characteristics in the fluidic flux.

In one embodiment of the invention, two three-dimensional chambers haveat least one inlet and at least one outlet port for the flow of a fluidinto and out of the chamber. The UV source is a planar source such as amicro plasma lamp, emitting UV radiation from both sides. The UV sourceis situated between the irradiation chamber and the cooling chamber andprovides radiation to both chambers. In one embodiment, the two chambersare in fluidic connection, where the inlet of one of the chambers is theoutlet for the other chamber. In another embodiment, each side of theplanar UV source serves as a portion of the sidewall of each chamber.

Referring now to the embodiment shown in FIGS. 11 and 12 , theirradiation apparatus F includes two three-dimensional chambers 37 and38, each having an inlet port and an outlet port for the flow of a fluidinto and out of the chambers. Irradiation chamber 37 has inlet port 40for fluid flow into the chamber and outlet port 41 for fluid flow out ofthe chamber. Cooling chamber 38 has inlet port 3 for fluid flow into thechamber and outlet port 40 for fluid flow out of the chamber. Coolingchamber 38 and irradiation chamber 37 are in fluidic connection and influid communication, with port 40 functioning as the outlet port for thecooling chamber and the inlet port for the irradiation chamber. UVradiation planar source 42 is a micro plasma lamp that providesradiation to the interior of irradiation chamber 37 and to the interiorof cooling chamber 38. The UV source is situated between the irradiationchamber and the cooling chamber and provides radiation to both chambers.Each side of the planar UV source serves as a portion of the sidewall ofeach chamber. The UV radiation source 42 has a quartz sleeve or opticalwindow covering each of its sides to protect it from fluid in theirradiation chamber and cooling chamber. The UV radiation source issealed between the windows such that the windows serve as a portion ofthe pressure vessel for the disinfection system and to segregate the UVradiation source from the fluid in the irradiation chamber.

In one embodiment, the irradiation chamber 37 is constructed from amaterial which principally reflects the UV radiation from the UV sourceand the cooling chamber 38 is constructed from a material whichprincipally absorbs UV radiation. In another embodiment, both theirradiation chamber 37 and cooling chamber 38 are constructed from amaterial which principally reflects the UV radiation from the UV source.In another embodiment, both the irradiation chamber 37 and coolingchamber 38 are constructed from a material which principally absorbs theJV radiation from the UV source.

In another embodiment of the invention, the UV source described hereinmay comprise a UV emitter, such as the UV emitter assembly G shown inFIGS. 13 and 14 . UV emitter 45 is embedded inside an environmentallysealed housing which partially or completely encloses the UV emitterbetween a thermal transfer material or conductor 44, such as a metalcore printed circuit board, and a UV transparent window 47. In anotherembodiment, the sealed housing comprises a principally UV transparentwindow, such as window 47, and a heatsink, such as a principallythermally conducting cup 43, that combine to form an enclosed volume inwhich one or more UV LEDs on a circuit board is located and which is inthermal connection to the cup. A potting compound 48 fills the voidbetween the thermally conductive cup and the window, less a small keepout area 46 around the perimeter of the LEDs. In one embodiment, thethermally conductive cup is created by deformation of a single metalsheet. The thermally conductive cup may have one or more ports forelectrical connection entry and/or exit and/or for the injection of aliquid potting compound. In another embodiment, the thermally conductivecup comprises at least one face intended principally for thermaltransfer to/from the UV emitter.

In other embodiments of the invention, the optically transparent windowis made of quartz or sapphire or a principally UV transparent polymer.The potting compound may principally retain the optically transparentwindow in the thermally conductive cup and serve as a structuralcomponent to the assembly. The UV emitter may comprise a UV radiationsource mounted on a substrate with a control system further mounted onthe substrate. The UV radiation source may comprise at least one of anLED, a plasma discharge source, or a solid-state phosphor emissiondevice, or combinations thereof. The substrate may comprise a printedcircuit board. The substrate may be designed to create an efficientthermal path between the UV radiation source and an external thermalreservoir. The substrate may provide a means of preventing contactbetween the potting compound and UV radiation source. The substrate mayprovide a means to fix relative positioning of the UV radiation sourceand the optically transparent window. A control system may comprise aconstant-current source or a constant-current sink.

Although the invention is illustrated and described herein withreference to certain embodiments and examples thereof it will be readilyapparent to those skilled in the art that other embodiments and examplesmay perform similar functions and/or achieve like results. Likewise, itwill be apparent that other applications of the disclosed technology arepossible. All such equivalent embodiments, examples, and applicationsare within the spirit and scope of the invention and are intended to becovered by the following claims.

We claim:
 1. An irradiation apparatus comprising: at least one irradiation chamber for a fluid containing a material to be irradiated, said chamber having at least one inlet port for fluid flow into the chamber and at least one outlet port for fluid flow out of the chamber; at least one cooling chamber having at least one inlet port for fluid flow into the chamber and at least one outlet port for fluid flow out of the chamber; one or more UV radiation sources coupled to the at least one irradiation chamber; one or more seals or gaskets disposed adjacent to the one or more radiation sources to protect the one or more radiation sources from the fluid in the irradiation apparatus and/or external environment; and at least one heat exchange mechanism thermally coupled to the one or more radiation sources and to the at least one cooling chamber.
 2. The irradiation apparatus of claim 1, wherein one seal is disposed adjacent to the one or more radiation sources to protect the one or more radiation sources from moisture in the irradiation apparatus, and another seal is disposed adjacent to the one or more radiation sources to protect the one or more radiation sources from moisture in the irradiation apparatus and/or external environment.
 3. The irradiation apparatus of claim 1, wherein one seal is disposed adjacent to the one or more radiation sources to protect the one or more radiation sources from liquid in the irradiation chamber, and another seal is disposed adjacent to the one or more radiation sources to protect the one or more radiation sources from moisture in the irradiation apparatus and/or external environment.
 4. The irradiation apparatus of claim 1, wherein the one or more UV radiation sources comprise one or more UV-C radiation sources, or a combination thereof.
 5. The irradiation apparatus of claim 1, wherein the one or more UV radiation sources comprise a plurality of radiation sources arranged in an array.
 6. The irradiation apparatus of claim 1, wherein one or more wavelengths of the one or more UV radiation sources are dynamically adjustable.
 7. The irradiation apparatus of claim 1, wherein the one or more UV radiation sources deliver a combination of wavelengths to the material to be irradiated.
 8. The irradiation apparatus of claim 1, comprising a plurality of UV radiation sources and a plurality of irradiation chambers, each with at least one inlet and one outlet port, and all of the UV radiation sources are thermally coupled to a single cooling chamber.
 9. The irradiation apparatus according to claim 1, wherein the one or more UV radiation sources are operated under dynamic control using a monitoring mechanism or control circuitry for dynamically controlling the delivery of UV radiation to the material to be irradiated based on liquid flow rate, water quality, user input, and/or other operating conditions.
 10. The irradiation apparatus of claim 9, wherein performance data are stored in an onboard or external data storage unit.
 11. The irradiation apparatus according to claim 2, wherein the one or more UV radiation sources are operated under dynamic control using a monitoring mechanism or control circuitry for dynamically controlling the delivery of UV radiation to the material to be irradiated based on liquid flow rate, water quality, user input, and/or other operating conditions.
 12. The irradiation apparatus according to claim 3, wherein the one or more UV radiation sources are operated under dynamic control using a monitoring mechanism or control circuitry for dynamically controlling the delivery of UV radiation to the material to be irradiated based on liquid flow rate, water quality, user input, and/or other operating conditions. 